Party membership and affiliation: Realizing party linkage and community in the twenty-first century

Since the turn of the century, the emergence of new (types of) parties and the organizational evolution of established ones has challenged traditional ideas of party membership with innovative forms of membership and affiliation. These shifts affect how parties build linkage and sustain their communities. While many studies focus on the changing nature of membership within individual parties, a comprehensive, comparative understanding of these changes - what is driving them, and how they impact the democratic functioning of political parties - is lacking. We establish a theoretical and empirical framework to investigate these phenomena that distinguishes between the concept of party membership (what it is supposed to achieve) and the way in which party membership is operationalized from the perspective of the state, parties as organizations and individuals. Our framework and illustrative examples serve as a foundation for the comprehensive empirical analysis undertaken by the contributors to this special issue.